J/ApJ/854/L14 Photometry and spectra of SN 2017dio (Kuncarayakti+, 2018) ================================================================================ SN 2017dio: a type-Ic supernova exploding in a hydrogen-rich circumstellar medium. Kuncarayakti H., Maeda K., Ashall C.J., Prentice S.J., Mattila S., Kankare E., Fransson C., Lundqvist P., Pastorello A., Leloudas G., Anderson J.P., Benetti S., Bersten M.C., Cappellaro E., Cartier R., Denneau L., Della Valle M., Elias-Rosa N., Folatelli G., Fraser M., Galbany L., Gall C., Gal-Yam A., Gutierrez C.P., Hamanowicz A., Heinze A., Inserra C., Kangas T., Mazzali P., Melandri A., Pignata G., Rest A., Reynolds T., Roy R., Smartt S.J., Smith K.W., Sollerman J., Somero A., Stalder B., Stritzinger M., Taddia F., Tomasella L., Tonry J., Weiland H., Young D.R. =2018ApJ...854L..14K (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Supernovae ; Photometry, SDSS ; Spectra, optical Keywords: supernovae: general - supernovae: individual (SN 2017dio) Abstract: SN 2017dio shows both spectral characteristics of a type-Ic supernova (SN) and signs of a hydrogen-rich circumstellar medium (CSM). Prominent, narrow emission lines of H and He are superposed on the continuum. Subsequent evolution revealed that the SN ejecta are interacting with the CSM. The initial SN Ic identification was confirmed by removing the CSM interaction component from the spectrum and comparing with known SNe Ic, and reversely, adding a CSM interaction component to the spectra of known SNe Ic and comparing them to SN 2017dio. Excellent agreement was obtained with both procedures, reinforcing the SN Ic classification. The light curve constrains the pre-interaction SN Ic peak absolute magnitude to be around Mg=-17.6mag. No evidence of significant extinction is found, ruling out a brighter luminosity required by a SN Ia classification. These pieces of evidence support the view that SN 2017dio is a SN Ic, and therefore the first firm case of a SN Ic with signatures of hydrogen-rich CSM in the early spectrum. The CSM is unlikely to have been shaped by steady-state stellar winds. The mass loss of the progenitor star must have been intense, dM/dt~0.02({epsilon}_Ha_/0.01)^-1^*(v_wind_/500km/s)* (v_shock_/10000km/s)^-3^M_{sun}_/yr, peaking at a few decades before the SN. Such a high mass loss rate might have been experienced by the progenitor through eruptions or binary stripping. Description: ugriz + JHK photometry and optical spectra of SN 2017dio. Optical photometry was obtained in ugriz filters using ALFOSC at the Nordic Optical Telescope (NOT), IO:O at the Liverpool Telescope (LT), and Spectral at the 2 m telescopes of Las Cumbres Observatory. JHK photometry was obtained using NOT/NOTCam at one epoch, 2017 July 27. Optical slit-spectroscopy was obtained using ALFOSC at the NOT, EFOSC2 at the ESO New Technology Telescope (NTT, through the ePESSTO program), and SPRAT 45 at the LT. ALFOSC spectra cover 3300-9500{AA}, with a resolution of 16{AA}. With EFOSC2, grism #13, the coverage was 3500-9300{AA}, at a 21{AA} resolution. Additionally, in two epochs the EFOSC2 spectra were taken using grism #11 (16{AA} resolution). SPRAT covers 4000-8000{AA}, with a 18{AA} resolution. Objects: ----------------------------------------- RA (2000) DE Designation(s) ----------------------------------------- 11 36 27.76 +18 17 46.92 SN 2017dio ----------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file ph17dio.dat 129 24 Photometry in ugriz + JHKs s170430.dat 27 1015 Spectrum on 2017-04-30 s170501.dat 28 1629 Spectrum on 2017-05-01 s170502.dat 27 1875 Spectrum on 2017-05-02 s170513.dat 27 433 Spectrum on 2017-05-13 s170514.dat 27 1875 Spectrum on 2017-05-14 s170523.dat 27 1875 Spectrum on 2017-05-23 s170601.dat 27 1629 Spectrum on 2017-06-01 s170619.dat 27 1875 Spectrum on 2017-06-19 s170718.dat 27 1875 Spectrum on 2017-07-18 -------------------------------------------------------------------------------- Byte-by-byte Description of file: ph17dio.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 10 A10 "date" Date Date of observation 12- 25 F14.8 d MJD MJD of observation 27- 32 F6.3 mag umag ?=- SDSS u-band magnitude 34- 38 F5.3 mag e_umag ?=- Error in SDSS u-band magnitude 40- 45 F6.3 mag gmag ?=- SDSS g-band magnitude 47- 51 F5.3 mag e_gmag ?=- Error in SDSS g-band magnitude 53- 58 F6.3 mag rmag ?=- SDSS r-band magnitude 60- 64 F5.3 mag e_rmag ?=- Error in SDSS r-band magnitude 66- 71 F6.3 mag imag ?=- SDSS i-band magnitude 73- 77 F5.3 mag e_imag ?=- Error in SDSS i-band magnitude 79- 84 F6.3 mag zmag ?=- SDSS z-band magnitude 86- 90 F5.3 mag e_zmag ?=- Error in SDSS z-band magnitude 92- 96 A5 --- Tel Telescope used for observation 98-102 F5.2 mag Jmag ?=- J-band magnitude 104-107 F4.2 mag e_Jmag ?=- Error in J-band magnitude 109-113 F5.2 mag Hmag ?=- H-band magnitude 115-118 F4.2 mag e_Hmag ?=- Error in H-band magnitude 120-124 F5.2 mag Kmag ?=- Ks-band magnitude 126-129 F4.2 mag e_Kmag ?=- Error in Ks-band magnitude -------------------------------------------------------------------------------- Byte-by-byte Description of file: s*.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 16 F16.11 0.1nm lambda Spectrum wavelength 18- 28 F11.8 10-2W/m2/nm Flux Spectrum flux (in erg/cm^2^/s/{AA}) -------------------------------------------------------------------------------- Acknowledgements: Hanindyo Kuncarayakti, kuncarayakti(at)gmail.com ================================================================================ (End) Patricia Vannier [CDS] 16-Feb-2018